The present disclosure concerns the analysis of forces that act upon a ground vehicle and, more particularly, a system for measuring forces within a rotating wheel assembly.
Traditional wind tunnels are valuable tools in determining how air flows around objects and ground vehicles. Testing the aerodynamics of ground vehicles, especially at the high speeds achieved by today's race cars, is affected by the stationary floor on which the ground vehicle rests in the wind tunnel. While rollers can and have been placed under the wheels to allow the wheels to turn at the proper speed, the air flow is still affected by the stationary boundary condition of the floor as the wind passes under and around the ground vehicle.
The development of “rolling road” wind tunnels has addressed the issue of the stationary floor by providing a moving surface under the ground vehicle. An example of a rolling road support floor is shown in FIG. 1. A continuous belt, typically a stainless steel sheet, passes around a pair of large rollers and under the test ground vehicle while supported by a series of smaller rollers. The ground vehicle rolls freely on the top of the belt and is held in place by restraint bars such as shown in FIGS. 2 and 3. Aerodynamic forces can be measured using load cells integrated into the restraint system. Ground vehicles can be tested at speeds in excess of 290 kilometers per hour (180 miles per hour).